It also is possible to restore to a smaller partition ( provided it is larger than the used space on the original partition). However , it takes a while, so if in doubt, shrink the source partition before making the image backup - then extend it again. Disk Management ( Vista/7 ) is good for that as although it will only shrink a limited amount ( it won't move system files ) - it is therefore very quick.

You also want to be careful with the operating system. If it was the first partition on the drive, and now on the second, the OS might not boot due to its new position, then you would have to run boot corrector from the CD or automatic repair from the Windows CD.